Exams › GATE › Technical

Consider the following four schedules due to three transactions (indicated by the subscript) using read and write on a data item x, denoted by r(x) and w(x) respectively. Which one of them is conflict serializable?

1. r1(x); r2(x); w1(x); r3(x); w2(x)
2. r2(x); r1(x); w2(x); r3(x); w1(x)
3. r3(x); r2(x); r1(x); w2(x); w1(x)
4. r2(x); w2(x); r3(x); r1(x); w1(x)

Correct answer: r2(x); w2(x); r3(x); r1(x); w1(x)

Solution

The correct option is conflict serializable because it can be transformed into a serial schedule without violating the order of conflicting operations. In this case, the writes and reads are arranged such that the dependencies between transactions do not create cycles, allowing for a consistent execution order.

Related GATE Technical questions

• Let G = (V,E) be a directed graph where V is the set of vertices and E the set of edges. Then which one of the following graphs has the same strongly connected components as G ?
• Consider the following program in C language: #include <stdio.h> main() { int i; int *pi = &i; scanf("%d", pi); printf("%d ", i+5); } Which one of the following statements is TRUE?
• Let G be a graph with n vertices and m edges. What is the tightest upper bound on the running time of Depth First Search on G, when G is represented as an adjacency matrix?
• Let P be a quicksort program to sort numbers in ascending order using the first element as the pivot. Let t1 and t2 be the number of comparisons made by P for the inputs [1 2 3 4 5] and [4 1 5 3 2] respectively. Which one of the following holds?
• Which one of the following is TRUE ?
• Match the following: 1) Waterfall model 2) Evolutionary model 3) Component-based software engineering 4) Spiral development a) Specifications can be developed incrementally b) Requirements compromises are inevitable c) Explicit recognition of risk d) Inflexible partitioning of the project into stages

⚔️ Practice GATE Technical free + battle 1v1 →